What’s actionable about “it’s everyone’s fault”?

If I'm having a problem with a server and you commented "Former sysadmin was dumb and lazy, so they misconfigured it" (and you're correct) is that constructive?

I think we mostly all agree that we as a society caused the problem, but we can't go back and undo that. Constructive would be coming up with ways we can, given the past did take place, improve things going forward.